Iron ores are
rocks and minerals from which metallic iron can be economically
extracted. The ores are usually rich in iron oxides and vary in
color from dark grey, bright yellow, deep purple, to rusty red. The
iron itself is usually found in the form of magnetite
(Fe3O4),
hematite (Fe2O3),
goethite (FeO(OH)), limonite (FeO(OH).n(H2O))
or siderite (FeCO3).
Ores carrying very high quantities of hematite or magnetite
(greater than ~*0% iron) are known as "natural ore" or "direct
shipping ore", meaning they can be fed directly into iron-making
blast furnaces. Most reserves of such ore have now been depleted.
Iron ore is the raw material used to make pig iron, which is one of
the main raw materials to make steel. *8% of the mined iron ore is
used to make steel. Indeed, it has been argued that iron ore is
"more integral to the global economy than any other commodity,
except perhaps oil"
